i tried to feed my bp a mouse last night, a small one. well it didnt want the meal. so i put the mouse in a tank to keep it until the snake is hungry. Today for some strange reason i was messin with the mouse and i noticed it has a pretty good sized lump on its back. is this safe to feed my snake? is this something i should be worried about from this pet store or is this common? there are no signs of a wound, just a lump.